1. Field of the Invention
The subject matter of the invention is a method for quantitative evaluation of agglutination reactions between a reagent and a biological fluid to be examined. The subject matter of the invention is, furthermore, an apparatus for carrying out the method, which is composed of an optical measuring arrangement of a light source, condenser, detecting device for a measuring field, objective and ground glass plate with an optoelectronic evaluating device.
2. Description of the Related Art
Agglutination reactions as a diagnostic method serve to protect and diagnose specific diseases such as myocardial infarcts, inflammations, rheumatoid factors etc. In the test required for the diagnosis, biological fluid such as blood serum is mixed manually with a specific antigen on a stained assay plate. After the reaction, the result is visually checked and evaluated diagnostically. In this process, the formation of agglutinates can be used to draw conclusions on the existence of corresponding antigens or antibodies. Apart from the specific biological properties of the proteins used, the significance of a positive or negative reaction depends strongly in this case on the judgment and experience of the particular experimenter or member of the laboratory staff. The disadvantage of this mode of procedure resides in that it is highly dependent upon the experience of the observer, there is limited measuring range and only yes/no statements on the result of the reaction are possible as a rule. Typically, no further-reaching statements can be made about quantifying the reaction.
Furthermore, DE-A-3,919,260 discloses a method for quantitative evaluation of agglutination reactions in which the agglutinates formed are detected optoelectronically and integrated over a fixed time interval. The thorough physical mixing of the reactants inside the fluid is performed by superimposing a tumbling movement and a rotational movement. A translation movement is superimposed on the tumbling movement during the optoelectronic measurement. The method permits the measurement of concentration-dependent, kinetic reaction processes and the quantifying of the agglutination reaction with the aid of appropriately constructed calibration curves. The disadvantage of this measurement method resides in the combination of a plurality of complicated processes of movement for the thorough mixing of the components inside the fluid, in the placing of the material to be measured in the beam path and in the superimposition of the tumbling movement with a translational movement during the optoelectronic measurement.